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Speed and call quality testTest delay, jitter and speed, with a focus on phone calls.My IP addressYour public IPv4 and IPv6 addresses, provider and address range.WhoIs lookupWho owns a domain or IP address, when it expires, and its DNS.DNS reportEvery DNS record for a domain, with email setup checked.IP subnet calculatorWork out a network's range, mask and hosts, and split it into subnets.

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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Prefix/16
Addresses2^112
/64 networks2^48
Network
2026::/16
First address
2026::
Last address
2026:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
5,192,296,858,534,827,628,530,496,329,220,096 (2^112)
/64 networks (LANs)
281,474,976,710,656 (2^48)
Full form
2026:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.2.0.2.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2026::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
12026::/242026:ff:ffff:ffff:ffff:ffff:ffff:ffff
22026:100::/242026:1ff:ffff:ffff:ffff:ffff:ffff:ffff
32026:200::/242026:2ff:ffff:ffff:ffff:ffff:ffff:ffff
42026:300::/242026:3ff:ffff:ffff:ffff:ffff:ffff:ffff
52026:400::/242026:4ff:ffff:ffff:ffff:ffff:ffff:ffff
62026:500::/242026:5ff:ffff:ffff:ffff:ffff:ffff:ffff
72026:600::/242026:6ff:ffff:ffff:ffff:ffff:ffff:ffff
82026:700::/242026:7ff:ffff:ffff:ffff:ffff:ffff:ffff
92026:800::/242026:8ff:ffff:ffff:ffff:ffff:ffff:ffff
102026:900::/242026:9ff:ffff:ffff:ffff:ffff:ffff:ffff
112026:a00::/242026:aff:ffff:ffff:ffff:ffff:ffff:ffff
122026:b00::/242026:bff:ffff:ffff:ffff:ffff:ffff:ffff
132026:c00::/242026:cff:ffff:ffff:ffff:ffff:ffff:ffff
142026:d00::/242026:dff:ffff:ffff:ffff:ffff:ffff:ffff
152026:e00::/242026:eff:ffff:ffff:ffff:ffff:ffff:ffff
162026:f00::/242026:fff:ffff:ffff:ffff:ffff:ffff:ffff
172026:1000::/242026:10ff:ffff:ffff:ffff:ffff:ffff:ffff
182026:1100::/242026:11ff:ffff:ffff:ffff:ffff:ffff:ffff
192026:1200::/242026:12ff:ffff:ffff:ffff:ffff:ffff:ffff
202026:1300::/242026:13ff:ffff:ffff:ffff:ffff:ffff:ffff
212026:1400::/242026:14ff:ffff:ffff:ffff:ffff:ffff:ffff
222026:1500::/242026:15ff:ffff:ffff:ffff:ffff:ffff:ffff
232026:1600::/242026:16ff:ffff:ffff:ffff:ffff:ffff:ffff
242026:1700::/242026:17ff:ffff:ffff:ffff:ffff:ffff:ffff
252026:1800::/242026:18ff:ffff:ffff:ffff:ffff:ffff:ffff
262026:1900::/242026:19ff:ffff:ffff:ffff:ffff:ffff:ffff
272026:1a00::/242026:1aff:ffff:ffff:ffff:ffff:ffff:ffff
282026:1b00::/242026:1bff:ffff:ffff:ffff:ffff:ffff:ffff
292026:1c00::/242026:1cff:ffff:ffff:ffff:ffff:ffff:ffff
302026:1d00::/242026:1dff:ffff:ffff:ffff:ffff:ffff:ffff
312026:1e00::/242026:1eff:ffff:ffff:ffff:ffff:ffff:ffff
322026:1f00::/242026:1fff:ffff:ffff:ffff:ffff:ffff:ffff
332026:2000::/242026:20ff:ffff:ffff:ffff:ffff:ffff:ffff
342026:2100::/242026:21ff:ffff:ffff:ffff:ffff:ffff:ffff
352026:2200::/242026:22ff:ffff:ffff:ffff:ffff:ffff:ffff
362026:2300::/242026:23ff:ffff:ffff:ffff:ffff:ffff:ffff
372026:2400::/242026:24ff:ffff:ffff:ffff:ffff:ffff:ffff
382026:2500::/242026:25ff:ffff:ffff:ffff:ffff:ffff:ffff
392026:2600::/242026:26ff:ffff:ffff:ffff:ffff:ffff:ffff
402026:2700::/242026:27ff:ffff:ffff:ffff:ffff:ffff:ffff
412026:2800::/242026:28ff:ffff:ffff:ffff:ffff:ffff:ffff
422026:2900::/242026:29ff:ffff:ffff:ffff:ffff:ffff:ffff
432026:2a00::/242026:2aff:ffff:ffff:ffff:ffff:ffff:ffff
442026:2b00::/242026:2bff:ffff:ffff:ffff:ffff:ffff:ffff
452026:2c00::/242026:2cff:ffff:ffff:ffff:ffff:ffff:ffff
462026:2d00::/242026:2dff:ffff:ffff:ffff:ffff:ffff:ffff
472026:2e00::/242026:2eff:ffff:ffff:ffff:ffff:ffff:ffff
482026:2f00::/242026:2fff:ffff:ffff:ffff:ffff:ffff:ffff
492026:3000::/242026:30ff:ffff:ffff:ffff:ffff:ffff:ffff
502026:3100::/242026:31ff:ffff:ffff:ffff:ffff:ffff:ffff
512026:3200::/242026:32ff:ffff:ffff:ffff:ffff:ffff:ffff
522026:3300::/242026:33ff:ffff:ffff:ffff:ffff:ffff:ffff
532026:3400::/242026:34ff:ffff:ffff:ffff:ffff:ffff:ffff
542026:3500::/242026:35ff:ffff:ffff:ffff:ffff:ffff:ffff
552026:3600::/242026:36ff:ffff:ffff:ffff:ffff:ffff:ffff
562026:3700::/242026:37ff:ffff:ffff:ffff:ffff:ffff:ffff
572026:3800::/242026:38ff:ffff:ffff:ffff:ffff:ffff:ffff
582026:3900::/242026:39ff:ffff:ffff:ffff:ffff:ffff:ffff
592026:3a00::/242026:3aff:ffff:ffff:ffff:ffff:ffff:ffff
602026:3b00::/242026:3bff:ffff:ffff:ffff:ffff:ffff:ffff
612026:3c00::/242026:3cff:ffff:ffff:ffff:ffff:ffff:ffff
622026:3d00::/242026:3dff:ffff:ffff:ffff:ffff:ffff:ffff
632026:3e00::/242026:3eff:ffff:ffff:ffff:ffff:ffff:ffff
642026:3f00::/242026:3fff:ffff:ffff:ffff:ffff:ffff:ffff
652026:4000::/242026:40ff:ffff:ffff:ffff:ffff:ffff:ffff
662026:4100::/242026:41ff:ffff:ffff:ffff:ffff:ffff:ffff
672026:4200::/242026:42ff:ffff:ffff:ffff:ffff:ffff:ffff
682026:4300::/242026:43ff:ffff:ffff:ffff:ffff:ffff:ffff
692026:4400::/242026:44ff:ffff:ffff:ffff:ffff:ffff:ffff
702026:4500::/242026:45ff:ffff:ffff:ffff:ffff:ffff:ffff
712026:4600::/242026:46ff:ffff:ffff:ffff:ffff:ffff:ffff
722026:4700::/242026:47ff:ffff:ffff:ffff:ffff:ffff:ffff
732026:4800::/242026:48ff:ffff:ffff:ffff:ffff:ffff:ffff
742026:4900::/242026:49ff:ffff:ffff:ffff:ffff:ffff:ffff
752026:4a00::/242026:4aff:ffff:ffff:ffff:ffff:ffff:ffff
762026:4b00::/242026:4bff:ffff:ffff:ffff:ffff:ffff:ffff
772026:4c00::/242026:4cff:ffff:ffff:ffff:ffff:ffff:ffff
782026:4d00::/242026:4dff:ffff:ffff:ffff:ffff:ffff:ffff
792026:4e00::/242026:4eff:ffff:ffff:ffff:ffff:ffff:ffff
802026:4f00::/242026:4fff:ffff:ffff:ffff:ffff:ffff:ffff
812026:5000::/242026:50ff:ffff:ffff:ffff:ffff:ffff:ffff
822026:5100::/242026:51ff:ffff:ffff:ffff:ffff:ffff:ffff
832026:5200::/242026:52ff:ffff:ffff:ffff:ffff:ffff:ffff
842026:5300::/242026:53ff:ffff:ffff:ffff:ffff:ffff:ffff
852026:5400::/242026:54ff:ffff:ffff:ffff:ffff:ffff:ffff
862026:5500::/242026:55ff:ffff:ffff:ffff:ffff:ffff:ffff
872026:5600::/242026:56ff:ffff:ffff:ffff:ffff:ffff:ffff
882026:5700::/242026:57ff:ffff:ffff:ffff:ffff:ffff:ffff
892026:5800::/242026:58ff:ffff:ffff:ffff:ffff:ffff:ffff
902026:5900::/242026:59ff:ffff:ffff:ffff:ffff:ffff:ffff
912026:5a00::/242026:5aff:ffff:ffff:ffff:ffff:ffff:ffff
922026:5b00::/242026:5bff:ffff:ffff:ffff:ffff:ffff:ffff
932026:5c00::/242026:5cff:ffff:ffff:ffff:ffff:ffff:ffff
942026:5d00::/242026:5dff:ffff:ffff:ffff:ffff:ffff:ffff
952026:5e00::/242026:5eff:ffff:ffff:ffff:ffff:ffff:ffff
962026:5f00::/242026:5fff:ffff:ffff:ffff:ffff:ffff:ffff
972026:6000::/242026:60ff:ffff:ffff:ffff:ffff:ffff:ffff
982026:6100::/242026:61ff:ffff:ffff:ffff:ffff:ffff:ffff
992026:6200::/242026:62ff:ffff:ffff:ffff:ffff:ffff:ffff
1002026:6300::/242026:63ff:ffff:ffff:ffff:ffff:ffff:ffff
1012026:6400::/242026:64ff:ffff:ffff:ffff:ffff:ffff:ffff
1022026:6500::/242026:65ff:ffff:ffff:ffff:ffff:ffff:ffff
1032026:6600::/242026:66ff:ffff:ffff:ffff:ffff:ffff:ffff
1042026:6700::/242026:67ff:ffff:ffff:ffff:ffff:ffff:ffff
1052026:6800::/242026:68ff:ffff:ffff:ffff:ffff:ffff:ffff
1062026:6900::/242026:69ff:ffff:ffff:ffff:ffff:ffff:ffff
1072026:6a00::/242026:6aff:ffff:ffff:ffff:ffff:ffff:ffff
1082026:6b00::/242026:6bff:ffff:ffff:ffff:ffff:ffff:ffff
1092026:6c00::/242026:6cff:ffff:ffff:ffff:ffff:ffff:ffff
1102026:6d00::/242026:6dff:ffff:ffff:ffff:ffff:ffff:ffff
1112026:6e00::/242026:6eff:ffff:ffff:ffff:ffff:ffff:ffff
1122026:6f00::/242026:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1132026:7000::/242026:70ff:ffff:ffff:ffff:ffff:ffff:ffff
1142026:7100::/242026:71ff:ffff:ffff:ffff:ffff:ffff:ffff
1152026:7200::/242026:72ff:ffff:ffff:ffff:ffff:ffff:ffff
1162026:7300::/242026:73ff:ffff:ffff:ffff:ffff:ffff:ffff
1172026:7400::/242026:74ff:ffff:ffff:ffff:ffff:ffff:ffff
1182026:7500::/242026:75ff:ffff:ffff:ffff:ffff:ffff:ffff
1192026:7600::/242026:76ff:ffff:ffff:ffff:ffff:ffff:ffff
1202026:7700::/242026:77ff:ffff:ffff:ffff:ffff:ffff:ffff
1212026:7800::/242026:78ff:ffff:ffff:ffff:ffff:ffff:ffff
1222026:7900::/242026:79ff:ffff:ffff:ffff:ffff:ffff:ffff
1232026:7a00::/242026:7aff:ffff:ffff:ffff:ffff:ffff:ffff
1242026:7b00::/242026:7bff:ffff:ffff:ffff:ffff:ffff:ffff
1252026:7c00::/242026:7cff:ffff:ffff:ffff:ffff:ffff:ffff
1262026:7d00::/242026:7dff:ffff:ffff:ffff:ffff:ffff:ffff
1272026:7e00::/242026:7eff:ffff:ffff:ffff:ffff:ffff:ffff
1282026:7f00::/242026:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1292026:8000::/242026:80ff:ffff:ffff:ffff:ffff:ffff:ffff
1302026:8100::/242026:81ff:ffff:ffff:ffff:ffff:ffff:ffff
1312026:8200::/242026:82ff:ffff:ffff:ffff:ffff:ffff:ffff
1322026:8300::/242026:83ff:ffff:ffff:ffff:ffff:ffff:ffff
1332026:8400::/242026:84ff:ffff:ffff:ffff:ffff:ffff:ffff
1342026:8500::/242026:85ff:ffff:ffff:ffff:ffff:ffff:ffff
1352026:8600::/242026:86ff:ffff:ffff:ffff:ffff:ffff:ffff
1362026:8700::/242026:87ff:ffff:ffff:ffff:ffff:ffff:ffff
1372026:8800::/242026:88ff:ffff:ffff:ffff:ffff:ffff:ffff
1382026:8900::/242026:89ff:ffff:ffff:ffff:ffff:ffff:ffff
1392026:8a00::/242026:8aff:ffff:ffff:ffff:ffff:ffff:ffff
1402026:8b00::/242026:8bff:ffff:ffff:ffff:ffff:ffff:ffff
1412026:8c00::/242026:8cff:ffff:ffff:ffff:ffff:ffff:ffff
1422026:8d00::/242026:8dff:ffff:ffff:ffff:ffff:ffff:ffff
1432026:8e00::/242026:8eff:ffff:ffff:ffff:ffff:ffff:ffff
1442026:8f00::/242026:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1452026:9000::/242026:90ff:ffff:ffff:ffff:ffff:ffff:ffff
1462026:9100::/242026:91ff:ffff:ffff:ffff:ffff:ffff:ffff
1472026:9200::/242026:92ff:ffff:ffff:ffff:ffff:ffff:ffff
1482026:9300::/242026:93ff:ffff:ffff:ffff:ffff:ffff:ffff
1492026:9400::/242026:94ff:ffff:ffff:ffff:ffff:ffff:ffff
1502026:9500::/242026:95ff:ffff:ffff:ffff:ffff:ffff:ffff
1512026:9600::/242026:96ff:ffff:ffff:ffff:ffff:ffff:ffff
1522026:9700::/242026:97ff:ffff:ffff:ffff:ffff:ffff:ffff
1532026:9800::/242026:98ff:ffff:ffff:ffff:ffff:ffff:ffff
1542026:9900::/242026:99ff:ffff:ffff:ffff:ffff:ffff:ffff
1552026:9a00::/242026:9aff:ffff:ffff:ffff:ffff:ffff:ffff
1562026:9b00::/242026:9bff:ffff:ffff:ffff:ffff:ffff:ffff
1572026:9c00::/242026:9cff:ffff:ffff:ffff:ffff:ffff:ffff
1582026:9d00::/242026:9dff:ffff:ffff:ffff:ffff:ffff:ffff
1592026:9e00::/242026:9eff:ffff:ffff:ffff:ffff:ffff:ffff
1602026:9f00::/242026:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1612026:a000::/242026:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
1622026:a100::/242026:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
1632026:a200::/242026:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
1642026:a300::/242026:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
1652026:a400::/242026:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
1662026:a500::/242026:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
1672026:a600::/242026:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
1682026:a700::/242026:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
1692026:a800::/242026:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
1702026:a900::/242026:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
1712026:aa00::/242026:aaff:ffff:ffff:ffff:ffff:ffff:ffff
1722026:ab00::/242026:abff:ffff:ffff:ffff:ffff:ffff:ffff
1732026:ac00::/242026:acff:ffff:ffff:ffff:ffff:ffff:ffff
1742026:ad00::/242026:adff:ffff:ffff:ffff:ffff:ffff:ffff
1752026:ae00::/242026:aeff:ffff:ffff:ffff:ffff:ffff:ffff
1762026:af00::/242026:afff:ffff:ffff:ffff:ffff:ffff:ffff
1772026:b000::/242026:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
1782026:b100::/242026:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
1792026:b200::/242026:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
1802026:b300::/242026:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
1812026:b400::/242026:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
1822026:b500::/242026:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
1832026:b600::/242026:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
1842026:b700::/242026:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
1852026:b800::/242026:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
1862026:b900::/242026:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
1872026:ba00::/242026:baff:ffff:ffff:ffff:ffff:ffff:ffff
1882026:bb00::/242026:bbff:ffff:ffff:ffff:ffff:ffff:ffff
1892026:bc00::/242026:bcff:ffff:ffff:ffff:ffff:ffff:ffff
1902026:bd00::/242026:bdff:ffff:ffff:ffff:ffff:ffff:ffff
1912026:be00::/242026:beff:ffff:ffff:ffff:ffff:ffff:ffff
1922026:bf00::/242026:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1932026:c000::/242026:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
1942026:c100::/242026:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
1952026:c200::/242026:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
1962026:c300::/242026:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
1972026:c400::/242026:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
1982026:c500::/242026:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
1992026:c600::/242026:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
2002026:c700::/242026:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
2012026:c800::/242026:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
2022026:c900::/242026:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
2032026:ca00::/242026:caff:ffff:ffff:ffff:ffff:ffff:ffff
2042026:cb00::/242026:cbff:ffff:ffff:ffff:ffff:ffff:ffff
2052026:cc00::/242026:ccff:ffff:ffff:ffff:ffff:ffff:ffff
2062026:cd00::/242026:cdff:ffff:ffff:ffff:ffff:ffff:ffff
2072026:ce00::/242026:ceff:ffff:ffff:ffff:ffff:ffff:ffff
2082026:cf00::/242026:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2092026:d000::/242026:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
2102026:d100::/242026:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
2112026:d200::/242026:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
2122026:d300::/242026:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
2132026:d400::/242026:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
2142026:d500::/242026:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
2152026:d600::/242026:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
2162026:d700::/242026:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
2172026:d800::/242026:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
2182026:d900::/242026:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
2192026:da00::/242026:daff:ffff:ffff:ffff:ffff:ffff:ffff
2202026:db00::/242026:dbff:ffff:ffff:ffff:ffff:ffff:ffff
2212026:dc00::/242026:dcff:ffff:ffff:ffff:ffff:ffff:ffff
2222026:dd00::/242026:ddff:ffff:ffff:ffff:ffff:ffff:ffff
2232026:de00::/242026:deff:ffff:ffff:ffff:ffff:ffff:ffff
2242026:df00::/242026:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2252026:e000::/242026:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
2262026:e100::/242026:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
2272026:e200::/242026:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
2282026:e300::/242026:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
2292026:e400::/242026:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
2302026:e500::/242026:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
2312026:e600::/242026:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
2322026:e700::/242026:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
2332026:e800::/242026:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
2342026:e900::/242026:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
2352026:ea00::/242026:eaff:ffff:ffff:ffff:ffff:ffff:ffff
2362026:eb00::/242026:ebff:ffff:ffff:ffff:ffff:ffff:ffff
2372026:ec00::/242026:ecff:ffff:ffff:ffff:ffff:ffff:ffff
2382026:ed00::/242026:edff:ffff:ffff:ffff:ffff:ffff:ffff
2392026:ee00::/242026:eeff:ffff:ffff:ffff:ffff:ffff:ffff
2402026:ef00::/242026:efff:ffff:ffff:ffff:ffff:ffff:ffff
2412026:f000::/242026:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
2422026:f100::/242026:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
2432026:f200::/242026:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
2442026:f300::/242026:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
2452026:f400::/242026:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
2462026:f500::/242026:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
2472026:f600::/242026:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
2482026:f700::/242026:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
2492026:f800::/242026:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
2502026:f900::/242026:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
2512026:fa00::/242026:faff:ffff:ffff:ffff:ffff:ffff:ffff
2522026:fb00::/242026:fbff:ffff:ffff:ffff:ffff:ffff:ffff
2532026:fc00::/242026:fcff:ffff:ffff:ffff:ffff:ffff:ffff
2542026:fd00::/242026:fdff:ffff:ffff:ffff:ffff:ffff:ffff
2552026:fe00::/242026:feff:ffff:ffff:ffff:ffff:ffff:ffff
2562026:ff00::/242026:ffff:ffff:ffff:ffff:ffff:ffff:ffff

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.